Cooling dynamo-electric machines.



'No. 837,033. I PATENTED NOV. 27, 1906.

. P. BUNET. COOLING DYNAMO ELECTRIC MACHINES.

APPLICATION FILED MAR.23. 1906. y

2 SHEETSSHEET Invehtor:

Paul Bunet,

' N0. 837,033. PATENTED NOV. 27, 1906.

P.BUNET. COOLING DYNAMO ELECTRIC MACHINES.

APPLIGATION FILED MAR.23. 1905.

2 SHEETS-SHEET 2.

Inventor" Paul Bunet',

v 'M/MQQM" and forming a part dynamo-electric machine, on which ismount-f ing capacity of conductors from which they .of the machine.

the outer surface of which are secured suitably insulated commutatorbars 6. The

UNITED-STATES PATENT OFFIOE.

PAUL BUNET, or PARIS, FRANCE, ASS'IGNOR TO GENERAL ELECTRIC.

- COMPANY, A CORPORATION OF NEW YORK.

COOLING DYNAMO-ELECTRIQ NIACHlNE S.

To all whom it may concern:

Be it known that I, PAUL BUNET, a citizen of France, residing at Paris,France, have invented certain new and useful Im rovements in CoolingDynamo-Electric achines, of which the following is a specification.

My present invention relates to means for coohng dynamo-elec icmachines, and especially to means for cooling the conductors thereof,such as the commutator-bars and the like.

In carrying out my invention I provide the conductors to be cooled withprojections,

referably formed of a metal which is a good eat-conductor. Theprojections PIOVldGd serve to materially increase the heat-radiatextenWhen the conductors are mounted on a movable portion of the machine, asis the ordinary case with commutator-bars, I prefer to form theprojections so that they serve as fan-blades or vanes to eneratecurrents of air, which serve to st' further cool the conductors. H j

The various features of. novelty which characterize my invention arepointedout with particularity in the claims annexed to this secification.

For a betterinnderstan g of my invention, however, reference 'may be hadto the accompanying drawings and descri tive matter, in which have ilustrated an described forms in which my invention may be embodied. i

. Referring to the drawings, Figure 1 is an elevation of adynamo-electric. machine embodying my invention with parts broken awayand in section. Fig. 2 is an elevation of a commutator-bar and projection employed in'a'modified construction. Fig. 3 a section of acommutator-bar and one form of attached projection. isan end elevationof the construction shown in Fig. 1'; and Fig. 5 is a view similar toFig. 2, showing another modification. H

In. the drawings, 1 represents the base of a ed a field-ring 2 andpillow-blocks 3, which is journaled a shaft 4, carrying the armature Atone end of the shaft 4 is mounted the usual commutator-shell 5, on

' Specification of Letters'Patent.

Application filed March 23, 1906. Satin-1N0. 251.576.

sheet metal or other sultable material,

Patented lflov. 27, 1906.

bars 6, which extend parallel to the axis of the shaft 4, are clampedbetween end clamping members 7, engaging the ends of the shell 5 andconnected together by bolts 8. The commutator-bars 6 may be of the usualform with the exception that to the upper side of some or all of thecommutatorbars radial projections 8 are secured.

In the constructionshown in Figs. 1 and 3 the projections are arrangedin three sets,

one set extending from each end of the bars and a set midway betweentheends of the bars. The projections 8 may be integral with the bars 6,thoughordinarily they are separate pieces rigidly secured thereto. In

Flg. 3 ofthe drawings I have shown a construction in which the lower endof the body of the rojection 8 is slightly less in thickness than t euppler surface of "the commutatorbar to who it is secured. The extreme,

lower end of the rojection 8 is reduced to form a tenon 9, w 'ch setsinto a socket or recess formed to receive it in the upper side of thecommutator-bar and is secured in by a transverse pin 9'. pin 9' thecommutator-bars and the projections may be connected by soldering. In

place some cases the pin may be dispensed with.

The conductors. 10, connecting the commutator-bars to thearmature-winding, may be secured to the-'commutator-bars in the samemanner as are the projections 8.

Instead of the construction shown in Fig. 3

same thickness as t e.port1on entering the In addition to the socket inthe commutator-bar. This isthe construction shown in Fig. 2. In theconstruction shown tater-bars, are carried in the usual manner from anannular support or yoke 12, which is secured against the field-ring 2 inthe usual 1n Flgs. 1 and 4;, the brushes 11, cooperating with the commuvor posts carried by the yoke 12 extend paral- I lel to the shaft 4 atvarious points about the 'lcommutator. These posts 14 are employed tosupport a number of annular shields-or members: 15, which 1117 be formedout of}.- V

the construction shown in. 1 and 4 a In- I V V F95 pair of shields 15are placed one at eachside of the left-hand set of rojections 8, one ateach side of the centra set of projections 8 and one to the left of theright-hand set of projections 8. The diameter of the opening in eachshield 15 is slightly greater than the internal diameter of thecommutator, so that the annular space is formed between the surface ofthe commutator and the inner peripheries of the guide-rings. When themachine is in operation, the rotation of the commutator causes theprojections 8 to generate aircurrents which flow into the chimney-spaceor fan-casings formed by the two pairs of disks 15 and by the right-handdisk 15 and the adjacent end of the armature from along the commutatorin the directions indicated by the arrows. The air is discharged fromthese chimney-spaces or fan-casings at the outer periphery of theguards. With this arrangement the commutator is cooled not onl by reasonof the good air circulation maintained, but because of the fact that theprojections 8, which are preferably formed of metalsuch as copper,brass, or the like, having a good heat conductivityserve to carry heataway from the commutator-bars by conduction. The rojections thus verymaterially increase t e heat-radiating capacity of the commutator. Ifdesired, the projectlons 8, arranged in the manner described, may be proortioned to produce a surface from which t e heat from eachcommutator-bar is radiated several times greater than that of theheat-radiating surface in the ordinary arrangement. The increasedheatdissipating capacity thus obtained is highly important, as thedisposition-of the heat generated by the friction of the brushes, thesparking between the brushes and the commutatorbars, and the currentscarried is fre uently the limiting factor in the output of t e machine.By the use of these projections in some cases other materials thancopper may sometimes be used for commutator-bars.

In the construction shown in Fig. '2 the commutator-bars 6' are providedwith only one set of heat-radiating projections 8, and the guards 15 aredispensed with. This arrangement of course possesses some of theadvantages of the construction shown in Fig. 1

. and Fi 3 and is simpler.

In t e construction shown in Fig. 5 the commutator-bars 6" formed.Heat-radiating and fan-blade projections 8 are secured to the ends ofthe bars of the two commutators adjacent each other. Blades 16,extending parallel to the shaft, are employed to connect the outer endsof adjacent extensions 8". Shield members 15, which may be similar toand be supported in the same manner as the shields 15 in theconstruction shown in Figs. 1 and 4, are

placed at opposite sides of the vanes formed are divided, so that, in'effect, two commutators placed end to end are by blades 16 and therejections 8", to which they are secured. IE will be seen that bysuitable proportioning of the parts shown in this construction a Veryowerl'ul draft can be maintained thro'u h t e chimney-spaces formedbetween the s ields 15.

It will be obvious to all those skilled in the art that many changes maybe made in the forms in which my invention is shown Without de artingfrom the spirit of my invention. or instance, the numbers of projectionssecured to each commutator-bar may be varied, and the projections may bechanged in configuration, and various means may be employed for securingthe projections to the bars. It will also be obvious that in some casesonly a portion of the commutator-bars in a commutator need be suppliedwith heat-radiating rojections.

While I have hereinbetoredescribed and illustrated the best forms of myinvention now known to me, I do not wish the" claims hereinafter made tobe limited by the particular construction illustrated more than is madenecessary by the state of the art. 7

What I claimas new, and desire to secure by Letters Patent of the UnitedStates, is-- 1. In a dynamo-electric machine, a commutator the bars ofwhich are rovided with heat-radiating projections an( a fan-casinginclosing said projections.

2. In a dynamo-electric machine, a rotating commutator provided withcommutatorbars which extend-parallel to the axis of rotation,heat-radiating pro'ections secured to the commutator-bars, an an annularmember surroundingthe commutator and serving to direct the air-currentsset in motion by said projections.

In a dynamo-electric machine, a rotating commutator comprisingcommutatorbars having fan-blades connected to them, and a pair ofannular members surrounding said commutator and arranged one at eachside of said fan-blades.

, 4. In a dynamo-electric machine, a rotat-- ing commutator comprisingcommutatorbars having fan-blades connected to them, and a pair ofannular members surrounding said commutator and arranged one at eachside of said fan-blades, said annular members being separated from thesurface of the commutator by s aces through which air may-be drawn by te fan-blades.

a dynamo-electric machine, a rotating commutator com risingcommutatorbars extending paralle to the axis of rotation and providedwith heat-radiating projections, and a fan-casing inclosing saidprojections.

6. \In adynamo-electric machine, a rotating commutator comprisingconductors or bars insulated from each other, and metal heat-radiatingprojections in the form of radial bars, the inner ends of which aresecured to said conductors or bars and the outer ends of which are free.a

7, In a dynamo-electric machine, a rotating commutator comprising aplurality of bars or conductors arranged parallel to the axis ofrotation, said bars having radial projections or extensions arranged sothat the bars rotate in the same plane transverse to the axis ofrotation, and a fan-casing therefor com rising a pair of annular memberssurroun g the commutator and located one at each side of theprojections.

8. In a dynamo-electric machine, a rotating commutator provided with-commutator bars extending parallel to the axis of rotation, one or moreof said commutator-bars being provided with extensions or projectionswhich serve to increase the heat-radiating capacity of the pair of barsto which they are attached, and a fan-casing surrounding said bars.

PAUL BUNET.

Witnesses:

WERNER HILDEBRAND, ARCHIBALD R. BAKER. I

